/a {add} def /m {mul} def
/pi 3.1415927 def
/clrs [[.2 0 .02][.9 .35 0][.02 .15 .5][.2 0 .02][.32 .36 .3][1 .76 .6]] def
306 396 translate .8 dup scale
/u {2 index sub abs .9 exch exp} def
/F {
  -187 25 188 {u 60 neg m a} for
  dup 2 m sin 45 m 3 2 roll a exch
  [-63 138] {u 60 m a} forall
  dup 2 m sin -90 m 3 2 roll a exch -12 a
  [-163 38 238] {u 60 m a} forall
  dup 2 m sin 45 m 3 2 roll a exch
} bind def
gsave
300 -4 2 {
  /ps 6.3 2 index .8 m m 5 m cvi def
  /d pi ps div 180 pi div m sin 2 m def
  0 2 copy newpath F moveto
  ps {
    dup 3 1 roll d m sub dup d m 3 2 roll a
    2 copy F lineto
  } repeat 
  /clrs [clrs aload pop dup aload pop setrgbcolor 6 1 roll] def
  pop pop closepath fill
} for
grestore
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